Scaling of the Resolving Power and Sensitivity for Planar FAIMS and Mobility-Based Discrimination in Flow- and Field- Driven Analyzers

Journal Article · Mon Sep 10 04:00:00 EDT 2007 · Journal of the American Society for Mass Spectrometry, 18(9):1672–1681

DOI:https://doi.org/10.1016/j.jasms.2007.06.013· OSTI ID:917958

Shvartsburg, Alexandre A; Smith, Richard D

Continuing rapid development of the technology and applications of field asymmetric waveform ion mobility spectrometry (FAIMS) calls for better understanding of the limitations of this method and factors that govern them. While key performance metrics such as resolution and ion transmission efficiency had been calculated for specific cases using numerical simulations, the underlying physical trends remained obscure. Here we determine that the resolving power of planar FAIMS scales as the square root of separation time and sensitivity drops exponentially at the rate controlled by absolute ion mobility and several instrumental parameters. A strong dependence of ion transmission on mobility causes severe discrimination against species with higher mobility, presenting particular problems for analyses of complex mixtures. While the time evolution of resolution and sensitivity is virtually identical in existing FAIMS systems driven by gas flow and proposed devices driven by electric field, the distributions of separation times are not. The inverse correlation between mobility (and thus diffusion speed) and residence time for a particular species in field-driven FAIMS greatly reduces the mobility-based discrimination and provides much more uniform separations.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 917958
• Report Number(s): PNNL-SA-55353; 20496; 400412000
• Journal Information: Journal of the American Society for Mass Spectrometry, 18(9):1672–1681, Journal Name: Journal of the American Society for Mass Spectrometry, 18(9):1672–1681 Journal Issue: 9 Vol. 18; ISSN 1044-0305; ISSN JAMSEF
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
DIFFUSION
Environmental Molecular Sciences Laboratory
ION MOBILITY
MASS SPECTROSCOPY
PERFORMANCE
RESOLUTION
SENSITIVITY